Search results for "Microelectrode"

showing 4 items of 64 documents

Contribution of area 19 to the foreground-background-interaction of the cat: an analysis based on single cell recordings and behavioural experiments.

1990

The contribution of area 19 to pattern discrimination in the cat was studied by single cell recordings in this area and by behavioural experiments before and after bilateral lesions. In order to make quantitative comparisons between behavioural performance and that of cell systems, we introduced a new parameter that characterizes visual neurons by their signal-to-noise (S/N) thresholds. A structured visual background made up of Gaussian visual broadband noise which could be moved was superimposed on the signal (moving bars or outline patterns) and the S/N characteristics of the response were determined by varying the signal intensity. The detection performance of cats after bilateral lesion…

medicine.medical_specialtyMotion PerceptionStimulus (physiology)AudiologyElectrocardiographymedicineImage noiseForeground-backgroundAnimalsVision OcularMathematicsVisual CortexNeuronsBehavior AnimalBroadband noiseGeneral NeuroscienceBrainPattern discriminationElectrophysiologyElectrophysiologyVisual cortexmedicine.anatomical_structurePattern Recognition VisualCatsDetection performanceFemaleNeuroscienceMicroelectrodesPhotic StimulationExperimental brain research
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Burst analysis tool for developing neuronal networks exhibiting highly varying action potential dynamics

2012

In this paper we propose a firing statistics based neuronal network burst detection algorithm for neuronal networks exhibiting highly variable action potential dynamics. Electrical activity of neuronal networks is generally analyzed by the occurrences of spikes and bursts both in time and space. Commonly accepted analysis tools employ burst detection algorithms based on predefined criteria. However, maturing neuronal networks, such as those originating from human embryonic stem cells (hESCs), exhibit highly variable network structure and time-varying dynamics. To explore the developing burst/spike activities of such networks, we propose a burst detection algorithm which utilizes the firing …

purskeanalyysispike trainsQuantitative Biology::Neurons and CognitiontoimintapotentiaalipurskeetMEAmicroelectrode arrayaction potential burstsdeveloping neuronal networksihmisalkion kantasoluhuman embryonic stem cellssoluttoimintapotentiaaliryhmätnervous systemhESCsmikroelektordihilakehittyvät hermoverkotburst analysis
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Spectral entropy based neuronal network synchronization analysis based on microelectrode array measurements

2016

Synchrony and asynchrony are essential aspects of the functioning of interconnected neuronal cells and networks. New information on neuronal synchronization can be expected to aid in understanding these systems. Synchronization provides insight in the functional connectivity and the spatial distribution of the information processing in the networks. Synchronization is generally studied with time domain analysis of neuronal events, or using direct frequency spectrum analysis, e.g., in specific frequency bands. However, these methods have their pitfalls. Thus, we have previously proposed a method to analyze temporal changes in the complexity of the frequency of signals originating from differ…

rat cortical cellsMEAmicroelectrode arrayspectral entropydeveloping neuronal networksmouse cortical cellssynchronizationkorrelaatio
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Comparison of local electrochemical impedance measurements derived frombi-electrode and microcapillary techniques

2009

Abstract In the present paper, local electrochemical impedance spectra were obtained on a 316L stainless steel from two configurations: a dual microelectrode (bi-electrode) and microcapillaries. With the bi-electrode, the local impedance measurements were made from the ratio of the applied voltage to the local current density calculated from the application of the ohm's law. With the use of microelectrochemical cells, the specimen surface area in contact with the electrolyte is limited by the use of glass microcapillaries and the local impedance was defined from the ratio of the local potential to the local current restricted to the analysed surface area. Differences and similarities observ…

spectroscopyLocal electrochemical impedanceChemistryGeneral Chemical EngineeringMatériauxAnalytical chemistryElectrolyteDielectric spectroscopyStainless steelMicroelectrodeElectrodeMicrocapillariesElectrochemistryEquivalent circuitBi-electrodesOhmComposite materialElectrical impedanceVoltage
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